AWS says disk is to cloud as tape is to disk

Amazon Web Services (AWS) says magnetic disks cannot handle modern NoSQL-powered applications, which have such high throughputs and generate such weirdly bursty traffic that spinning rust looks and feels as slow and awkward as tape.

“Magnetic disks are rapidly starting to exhibit tape-like properties and with modern workloads being increasingly random, they are becoming less and less suitable as a storage system.”

The comments need to be taken with a pinch of salt, given that the cloudy company has just announced “High I/O EC2” instances, which it says pack “2 TB of local SSD-backed storage, visible to you as a pair of 1 TB volumes”.

Performance looks sharp, at “120,000 random read IOPS and between 10,000 and 85,000 random write IOPS, both with 4K blocks” when working with PV virtualisation. If using HVM and Windows AMIs “you can expect 90,000 random read IOPS and 9,000 to 75,000 random write IOPS.”

The numinous nerds at AWS are spruiking the new flash-powered instances as ideal for large scale web apps, as Vogels says “DBMS’s can be very demanding. Increasingly randomized access and burst IO through aggregation put strains on any IO subsystem, physical or virtual, attached or remote. One area where we have seen this particularly culminate is in modern NoSQL DBMSs that are often the core of scalable modern web applications that exhibit a great deal of random access patterns.”

The new servers don’t seem cheap, given the pennies-per-hour standards some cloud services offer. But at either US$3.10 or US$3.41 an hour, depending on whether you chose AWS’ US East (Northern Virginia) or EU West (Ireland) sites, there’s a lot of grunt for the buck on offer.

We’re assuming the Ireland-based service is more expensive because it is not prone to the electrical storms that recently took down an AWS data centre in Virginia, taking Netflix with it. AWS is staring us all down on that score: Vogels’ post links to a Netflix testimonial about its love for AWS. ®